Industrial gas fuel turbines are located in a wide variety of environments. Some environmental effects can cause either the formation of rust on the interior passages of fuel nozzles of infrequently operated gas fuel turbines, or the ingestion of sand particles into internal passages of normally operated gas fuel turbines located in dusty areas. The entrainment of these particles into the fuel nozzle passages, specifically in the atomizing air passages, and when sufficiently accelerated and swirled, will impact the atomizing air injection tips of the nozzles at high speeds and thus cause erosion. The erosion rates of these air tips varies greatly with location, i.e., environment, with some nozzle tips lasting until the next scheduled inspection. In some cases, however, the erosion rate of the atomizing air tips is high enough to cause unscheduled shut-downs of operating turbines due to deterioration of fuel nozzle performance. As will be appreciated, unscheduled shut-downs are not only an inconvenience to the operator, but also cause lost revenue.
Ceramic materials are currently being used for high pressure particle nozzles for sandblast applications. There has also been some utilization of ceramic nozzles for diesel operations involving coal slurry fuels. To the best of applicant's knowledge, however, no one has previously attempted to utilize ceramic materials in fuel nozzles of gas turbine engines.